Principles, concepts, and perspectives for the improvement of decompression procedures: a Neo-Haldanian approach bridging bubble physics and decompression physiology

Introduction This paper is a narrative review and theoretical perspective presenting principles, concepts, and perspectives for improving decompression procedures. It distinguishes three levels of evidence: established observations, hypotheses with experimental support, and mechanistic scenarios that remain hypothetical. Methods We organize decompression around two linked dimensions: bubbles as the primary physical event and microparticles (MPs) as a physiological consequence. We hypothesize that a substantial proportion of decompression-related microbubbles originate from pre-existing gas micronuclei associated with active hydrophobic sites (AHS) at three locations: distal arterial, venous, and extravascular. From these assumptions, five bubble scenarios are considered: growth and detachment from distal arterial AHS; growth and detachment from venous AHS; pulmonary bubble filtration; survival of arterial gas microbubbles and their potential target organs; and intravascular bubble development. Physiological factors may generate MPs, endothelial dysfunction, systemic inflammation, and possibly a secondary generation of microbubbles. Results and discussion The proposed scenarios align with decompression sickness (DCS) pathophysiology across five target organ systems: skin, brain, inner ear, spinal cord, and musculoskeletal tissue. Inflammatory stress appears important for defining post-dive intervals and multiday diving patterns. Designing decompression procedures therefore requires integrating individual variability and dive history; dive characteristics such as rapid ascents, yo-yo diving, and surface decompression; the bubble scenarios triggered during ascent; and accumulated oxidative stress, oxy-inflammation, and endothelial damage that modify susceptibility to DCS. Conclusion There is no single ultimate decompression algorithm; rather, different strategies reflect different experience, assumptions, and operational contexts.